U.S. patent number 6,490,153 [Application Number 09/370,121] was granted by the patent office on 2002-12-03 for computer system for highly-dense mounting of system components.
This patent grant is currently assigned to California Digital Corporation. Invention is credited to Matthew P. Casebolt, Robert E. Ogrey.
United States Patent |
6,490,153 |
Casebolt , et al. |
December 3, 2002 |
Computer system for highly-dense mounting of system components
Abstract
A computer system with densely-mounted components and effective
cooling is provided. A hard drive mounting structure for "hot swap"
hard drives utilizes a hard drive assembly in which a hard drive is
mounted between a pair of parallel rails connected by a retaining
portion. The rails provide a precise mechanism for loading and
unloading the "hot swap" drive, without increasing the overall
height of each hard drive assembly. A handle with double-cam
actuation is used during insertion and removal of the hard drive
assembly. In accordance with the present invention, two half-height
hard drives may be stacked in a server mountable in a 2U rack. A
tool-less lock is provided for releasably securing expansion cards
to the computer case without the use of screws.
Inventors: |
Casebolt; Matthew P. (Fremont,
CA), Ogrey; Robert E. (San Jose, CA) |
Assignee: |
California Digital Corporation
(Fremont, CA)
|
Family
ID: |
23458313 |
Appl.
No.: |
09/370,121 |
Filed: |
August 6, 1999 |
Current U.S.
Class: |
361/679.33;
361/679.58; 361/724 |
Current CPC
Class: |
G06F
1/184 (20130101); G06F 1/187 (20130101); G11B
33/128 (20130101) |
Current International
Class: |
G06F
1/18 (20060101); G06F 001/16 () |
Field of
Search: |
;361/683-687,753,724-731,736-742,748,752,756,758,770 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Schuberg; Darren
Assistant Examiner: Chang; Yean-Hsi
Attorney, Agent or Firm: Skjerven Morrill LLP Woo; Philip
W.
Claims
We claim:
1. A computer system, comprising: a case including a first drive
bay; and a first drive assembly removably mounted in the first
drive bay, said first drive assembly comprising: a first hard
drive; and a first drive chassis, comprising: a first rail provided
along a first side of the first hard drive; a second rail
substantially parallel to the first rail and provided along a
second side of the first hard drive opposite the first side; a
retaining portion adjacent a front side of the first hard drive and
connecting a front end of the first rail to a front end of the
second rail, the retaining portion comprising a top plate and a
bottom plate; a first notch provided on a first interior side of
the first drive bay; a handle rotatably connected to the retaining
portion of the first drive chassis and between the top plate and
the bottom plate, the handle having a first end and a second end
distal from the first end, said handle being rotatable about an
axis perpendicular to the top and bottom plates and located between
the first and second ends of the handle, said handle defining a
closed position in which the first end of said handle is a first
distance from the front end of the first rail of the first drive
assembly, and said handle defining an open position in which the
handle is rotated about the axis such that the first end of the
handle is a second distance from the front end of the first rail of
the first drive assembly, the first distance being less than the
second distance; and a first latch provided on the first end of the
handle and adapted to engage the first notch when the first drive
assembly is inserted into the first drive bay and the handle is in
the closed position; wherein the first drive chassis does not
include any portion which is adjacent to a top surface and a bottom
surface of the first hard drive.
2. The computer system of claim 1, further comprising: a second
drive bay provided beneath the first drive bay; and a second drive
assembly removably mounted in the second drive bay, said second
drive assembly comprising: a second hard drive; and a second drive
chassis, comprising: a first rail provided along a first side of
the second hard drive; a second rail substantially parallel to the
first rail and provided along a second side of the second hard
drive opposite the first side; and a retaining portion adjacent a
front side of the second hard drive and connecting a front end of
the first rail to a front end of the second rail; wherein the
second drive chassis does not include any portion which is adjacent
to a top surface and a bottom surface of the second hard drive.
3. The computer system of claim 2, wherein a lower plane of the
first hard drive is separated from an upper plane of the second
hard drive by less than about 0.1 inches.
4. The computer system of claim 2, wherein: the case includes a top
cover and a bottom cover; an upper plane of the first hard drive is
separated from the top cover by less than about 0.1 inches; and a
lower plane of the second drive assembly is separated from the
bottom cover by less than about 0.1 inches.
5. The computer system of claim 2, wherein the second hard drive is
a half-height hard drive.
6. The computer system of claim 2, wherein the second drive bay is
adapted to receive a half-height hard drive.
7. The computer system of claim 2, further comprising: a first
guide rail provided on a first interior side of the second drive
bay for receiving the first rail of the second drive assembly; and
a second guide rail provided on a second interior side of the
second drive bay opposite the first interior side for receiving the
second rail of the second drive assembly.
8. The computer system of claim 1, wherein said case is
approximately 3.5 inches tall.
9. The computer system of claim 1, wherein the case is adapted to
be mounted in a 2U rack mount.
10. The computer system of claim 1, wherein the first hard drive is
a half-height hard drive.
11. The computer system of claim 1, wherein the first drive bay is
adapted to receive a half-height hard drive.
12. The computer system of claim 1, further comprising: a first
pair of guide rails provided on a first interior side of the first
drive bay for receiving the first rail of the first drive assembly;
and a second pair of guide rails provided on a second interior side
of the first drive bay opposite the first interior side for
receiving the second rail of the first drive assembly.
13. The computer system of claim 1, further comprising: a shoulder
provided on a second interior side of the first drive bay opposite
the first interior side; and a cam provided at the second end of
the handle and adapted to abut the shoulder when the first drive
assembly is inserted into the first drive bay.
14. The computer system of claim 13, wherein the first drive
assembly further comprises: a spring providing a force on the
handle, urging the handle to rotate from the closed position to the
open position.
15. The computer system of claim 13, further comprising: a second
notch provided on the second interior side of the first drive bay;
a second latch provided on the second end of the handle and adapted
to engage the second notch when the first drive assembly is
inserted in the first drive bay.
16. The computer system of claim 1, further comprising a fan
provided in the case adjacent a rear portion of the first drive
bay, said fan creating an airflow from a front side of the first
drive assembly to a rear side of the first drive assembly.
17. The computer system of claim 1, wherein a top portion of the
case is formed of thin gauge sheet metal less than approximately
0.05 inches thick.
18. The computer system of claim 1, wherein a bottom portion of the
case is formed of thin gauge sheet metal less than approximately
0.05 inches thick.
19. The computer system of claim 1, further comprising, in the
first rail of the first drive chassis, a light transmitting member
for transmitting light from a rear portion of the first drive bay
to a front portion of he first hard drive.
20. The computer system of claim 19, wherein: the first rail of the
first drive chassis defines a channel extending from a rear portion
of the first hard drive to the front portion of the first hard
drive; and the light transmitting member is a fiber optic filament
provided in the channel.
21. The computer system of claim 1, further comprising, in the
second rail of the first drive chassis, a light transmitting member
for transmitting light from a rear portion of the first drive bay
to a front portion of the first hard drive.
22. The computer system of claim 21, wherein: the second rail of
the first drive chassis defines a channel extending from a rear
portion of the first hard drive to the front portion of the first
hard drive; and the light transmitting member is a fiber optic
filament provided in the channel.
23. A hard drive mounting structure, comprising: a hard drive bay
including: a first notch provided on a first interior side of said
hard drive bay; and a shoulder provided on a second interior side
of said hard drive bay opposite the first interior side; and a hard
drive assembly, comprising: a hard drive; a chassis attached to the
hard drive, said chassis including a retaining portion positioned
adjacent a front portion of the hard drive, the retaining portion
comprising a top plate and a bottom plate; a handle rotatably
connected to the retaining portion between the top plate and the
bottom plate, the handle having a first end and a second end distal
from the first end, said handle being rotatable about an axis
perpendicular to the top and bottom plates and located between the
first and second ends of the handle, said handle defining a closed
position in which the first end of said handle is a first distance
from the chassis, and said handle defining an open position in
which the handle is rotated about the axis such that the first end
of the handle is a second distance from the chassis, the first
distance being less than the second distance; a first latch
provided on the first end of the handle and adapted to engage the
first notch when the hard drive assembly is inserted into the hard
drive bay and the handle is in the closed position; and a cam
provided at the second end of the handle and adapted to abut the
shoulder when the hard drive assembly is inserted into the hard
drive bay.
24. The hard drive mounting structure of claim 23, wherein the hard
drive assembly further comprises: a spring providing a force on the
handle, urging the handle to rotate from the closed position to the
open position.
25. The hard drive mounting structure of claim 23, further
comprising: a second notch provided on the second interior side of
the hard drive bay; a second latch provided on the second end of
the handle and adapted to engage the second notch when the hard
drive assembly is inserted in the hard drive bay.
26. The hard drive mounting structure of claim 23, wherein the
chassis comprises: a first rail provided along one side of the hard
drive; a second rail provided along an opposite side of the hard
drive; wherein the retaining portion is attached to a front end of
the first rail and a front end of the second rail.
27. The hard drive mounting structure of claim 23, wherein the
chassis does not include any portion which is adjacent to a top
surface and a bottom surface of the hard drive.
28. The hard drive mounting structure of claim 23, further
comprising: a first guide rail provided on the first interior side
of the hard drive bay for receiving the first rail of the hard
drive assembly; and a second guide rail provided on the second
interior side of the first drive bay for receiving the second rail
of the hard drive assembly.
29. The hard drive mounting structure of claim 23, wherein the hard
drive is a half-height hard drive.
30. The hard drive mounting structure of claim 23, further
comprising a fan adjacent a rear portion of the hard drive bay,
said fan creating an airflow from a front side of the hard drive
assembly to a rear side of the hard drive assembly.
Description
FIELD OF THE INVENTION
This invention relates to computer systems, and more specifically,
the design and layout of components of computer systems.
BACKGROUND
With the growth of computing applications, there has been an
associated increase in the need for servers and larger scale
computer systems. These server systems include such components as
CPUs, hard drives, CD-ROMs, DVDs, tape backup systems, peripheral
cards, monitors, and universal power supplies. Network servers
require a significant amount of storage capacity, typically in the
form of hard disk drives. A single server may use many hard disk
drives to increase the total storage capacity, or, in an
arrangement known as a Redundant Array of Inexpensive Disks
("RAID"), to provide secure data redundancy. In a RAID system, if
one hard drive fails, information in the other drives is used to
recover the lost data. Some RAID systems provide for "hot
swapping," in which a failed hard drive can be replaced and the
lost data reconstructed from the remaining drives without powering
down the system.
"Hot swap" drives include several characteristics not normally
required by conventional PC hard drives. "Hot swap" drives require
greater accessibility than conventional drives, which are typically
mounted in the computer chassis and attached to an internal hard
drive bay. It is desirable to place the "hot swap" drives in easily
accessible bays, mounted such that they are readily removable
without having to open the computer case. It is additionally
desirable that the drives be capable of making proper electrical
connections with the network computer when being replaced. When the
interface connectors on the hard drive are not properly mated to
their corresponding connectors, connector pin damage or failures
caused by intermittent breaks in the electrical transmissions
between the computer and the drive may result.
The various server components can be mounted vertically on a server
rack or cabinet in a dedicated server location, often with
temperature, humidity, and particle controls. Using such racks,
server components can be stored with high space efficiency, while
allowing easy visual and manual access. Server racks and cabinets
have standard size mounting holes to which computer equipment can
be attached. Rack-mounted equipment are typically provided in "U"
sizes. A 1U sized component measures 1.75" high, 19.00" wide, and
20.00" deep, while a 2U sized component is 3.5" high. These slim
form factors allow a larger number of devices to be mounted on a
given rack. However, these slim cases pose difficult design
problems for engineers attempting to add additional components into
the limited available space. For larger components, such as
monitors, RAID disk arrays, or larger servers, the rack must be
provided with taller openings, such as a 4U or 6U rack.
One type of server manufactured and sold by the assignee of this
invention is the VArServer 700. The body of the VArServer 700 is
provided with five hard drive bays into which half-height hard
drives can be mounted to form a RAID array. Hard drives sold by
different manufacturers are typically provided in standard sizes,
thus allowing the hard drives from different manufacturers to be
used interchangeably. Half-height hard drives are 1.625" tall and
are often chosen for server systems because of their increased
storage capacity (up to 36 GB, at the time of this application's
filing). The drives in the VArServer 700 are mounted in two stacks
of two drives, plus a single drive. Because of the size of the
array of hard drives and the thickness of the drives and the
related mounting structure, the server requires a tall 4U
chassis.
Another type of server manufactured and sold by the assignee of
this invention is the VArServer 500. The VArServer 500 has a
compact 2U form factor, which limits the size of the hard drives
its chassis can accommodate. Because of its limited size, the
VArServer 500 may utilize "low profile" drives, which are
approximately 1.0" high, rather than the half-height drives
preferred in server systems.
It is also known to mount different size drives in a single case.
In one type of system, a low profile drive is mounted on top of a
half-height drive in a 2U case. Although this provides increased
storage capacity over a system using only low profile drives, a
disadvantage of this system is that the low profile and half-height
drives cannot be used interchangeably. In particular, this limits
the type of "hot swapping" that can be used for this server.
Hard drives are not the only system components that create
challenges for design engineers. High-end computer systems may
utilize numerous expansion cards, such as video accelerators or
network cards. These cards plug into expansion slots using various
methods well known in the art. These cards are referred to as "PCI
cards," because they often operate in conjunction with a PCI bus on
a computer. As the number of components increase, while the amount
of available space inside the server case decreases, providing
secure mounts and expansion slots for such cards poses a
significant problem.
Another limiting factor with high-end computing systems is ensuring
effective heat dissipation from the various hardware components. In
particular, the central processing unit and the electrical
components mounted on the various circuit boards in the computer
system generate large amounts of heat. Without proper cooling,
these components can fail or can cause other components mechanisms
to fail. One conventional method of cooling these components is the
use of a fan mounted on a side of the chassis to force air to flow
from outside the chassis into and over the circuit boards. In a
given chassis, this method is effective when the number and size of
the components to be cooled are small. However, as more and more
components are squeezed into smaller server cases, it becomes
increasingly difficult to create an effective airflow. In addition,
these additional components increase the overall cooling
requirements of the system.
SUMMARY OF THE INVENTION
In accordance with the present invention, a computer system with
densely-mounted components and effective cooling is provided. In
one embodiment, a hard drive mounting structure for "hot swap" hard
drives utilizes a hard drive assembly in which a hard drive is
mounted between a pair of parallel rails connected by a retaining
portion. The rails provide a precise mechanism for loading and
unloading the "hot swap" drive, without increasing the overall
height of each hard drive assembly. A handle with double-cam
actuation is used during insertion and removal of the hard drive
assembly. In accordance with the present invention, two half-height
hard drives may be stacked in a server mountable in a 2U rack.
A computer system for highly dense mounting of components is
provided, wherein the computer system comprises a case including a
drive bay and a drive assembly removably mounted in the first drive
bay, wherein the drive assembly of the computer system comprises a
hard drive and a hard drive chassis. The hard drive chassis
comprises a first rail provided along a first side of the hard
drive; a second rail substantially parallel to the first rail and
provided along a second side of the hard drive opposite the first
side; and a retaining portion adjacent a front side of the hard
drive and connecting a front end of the first rail to a front end
of the second rail; wherein the top and bottom portions of the hard
drive are not covered by the hard drive chassis.
In another aspect of the present invention, a first notch is
provided on a first interior side of the first drive bay; a
shoulder is provided on a second interior side of the first drive
bay opposite the first interior side; a handle is rotatably
connected to the retaining portion of the first drive chassis and
has a first end and a second end distal from the first end. The
handle is rotatable about an axis located between the first and
second ends of the handle. The handle defines a closed position in
which the first end of said handle is a first distance from the
front end of the first rail of the first drive assembly, and
defines an open position in which the handle is rotated about the
axis such that the first end of the handle is a second distance
from the front end of the first rail of the first drive assembly,
the first distance being less than the second distance. A first
latch is provided on the first end of the handle and adapted to
engage the first notch when the first drive assembly is inserted
into the first drive bay and the handle is in the closed position;
and a cam is provided at the second end of the handle and adapted
to abut the shoulder when the first drive assembly is inserted into
the first drive bay.
In another aspect of the present invention, a clip for retaining
expansion boards is provided, wherein the retaining clip comprises
a clip body; a stabilizing projection attached to a top portion of
the clip body, adapted to be mounted on a computer case such that
said stabilizing projection is positioned on an exterior of the
case and the clip body is positioned on an interior of the case;
and a first flange attached to a side of the clip body and adapted
to abut a first expansion board, thereby preventing horizontal
movement of the first expansion board.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows a server in accordance with one aspect of the present
invention.
FIG. 2 illustrates an exemplary hard drive assembly with the handle
in the closed position.
FIG. 3 illustrates another view of the exemplary hard drive
assembly with the handle in the open position.
FIG. 4 illustrates an enlarged view of an empty hard drive bay.
FIGS. 5A-5C illustrate the operation of the handle, cam, and
latching mechanism for insertion and removal of the hard drive
assembly into the hard drive bay.
FIG. 6 illustrates a rear perspective view of a partially-exposed
server.
FIG. 7 illustrates a close-up view of an expansion card retainer in
the system case.
FIGS. 8A-8D illustrate multiple perspectives of the expansion card
retainer.
DETAILED DESCRIPTION
As shown in FIG. 1, server 50 is mounted in a 2U space on rack 52
(partially illustrated in FIG. 1). Server 50 includes five "hot
swap" hard drives 58 (FIG. 2) provided in interchangeable hard
drive assemblies 54, and one removable media drive 56, shown in
FIG. 1 as a floppy disk drive. Alternatively, the bay in which
removable media drive 56 is mounted can include a CD-ROM drive, a
DVD drive, or yet another hard drive assembly 54.
Hard drive assembly 54 is shown in greater detail in FIG. 2.
Assembly 54 includes hard drive 58 mounted in hard drive chassis
60. Hard drive 58 is shown in FIG. 2 as a featureless box, but in
actuality is a half-height hard drive including various surface
features. As is well known in the art, hard drive 58 typically
includes a sealed aluminum case with an electronic circuit board
attached on the bottom. An interface connector (not shown) is
provided on a rear portion of hard drive 58, and it includes pins
which mate with an interface 59 provided in hard drive bay 98 (FIG.
4). Although the upper and lower surfaces of hard drive 58 have a
varied topography, the highest points on these surfaces define the
upper and lower planes of hard drive 58, as illustrated by the
flat., featureless surfaces of hard drive 58 in FIG. 2.
In accordance with one aspect of the present invention, hard drive
chassis 60 includes first rail 61 and second rail 62, attached to
opposite sides of hard drive 58 using screws 64. In one embodiment,
rails 61, 62 are made of aluminum with a hard, anodized coating,
and measure 0.1".times.0.5".times.7.0".
Rails 61, 62 include channels 66 into which "light pipes" 68 are
provided. Light pipes 68 are fiber optic filaments for transmitting
light from the back of hard drive assembly 54 to the front end of
assembly 54. When hard drive assembly 54 is mounted in hard drive
bay 98 (FIG. 4), the back end of light pipes 68 are positioned
adjacent light sources in the back end of drive bay 98. These light
sources indicate the status of the mounted drive. Light pipes 68
transmit the status information from the back of the assembly 54 to
the front, where the light can be seen by a computer operator to
indicate, for example, whether the drive is in use (i.e., having
read/write disk activity) or has failed. Assembly 54 in FIG. 2
includes two light pipes 68 in each rail 61, 62. In practice,
however, any number of light pipes 68 may be used, and they may be
provided in one rail.
Hard drive chassis 60 also includes a retaining portion 70 provided
adjacent to the front portion of hard drive 58. Retaining portion
70 is connected to first and second rails 61, 62 and includes face
plate 72, top plate 74, and bottom plate 76. Face plate 72 includes
holes 80, which allow ambient air to be drawn into assembly 54 to
cool hard drive 58 and other components mounted in server 50. Top
plate 74 and bottom plate 76 are connected to the top and bottom
edges, respectively, of face plate 72, and have mounted between
them handle 78.
Handle 78 is rotatably mounted to top plate 74 and bottom plate 76
to rotate about axis 82. First latch 84 is provided on one end of
handle 78, and second latch 88 is provided on the opposite end.
First latch 84 is adapted to engage first notch 92 (FIG. 4) in hard
drive bay 98, and is released when a force is applied to latch pull
86. Second latch 88 is adapted to engage a second notch (not
shown), provided on the opposite side of hard drive bay 98 from
first notch 92. Cam 90 is provided on handle 78 adjacent to second
latch 88. Spring 96 (FIG. 3) provides a constant spring force
urging handle 78 to rotate into the open position such that first
latch 84 is moved outwards, away from hard drive 58.
The insertion process for assembly 54 and the operation of handle
78 are as follows. FIG. 4 shows empty hard drive bay 98 of server
50. When assembly 54 is not mounted in bay 98, handle 78,of hard
drive assembly 54 is urged by spring 96 to remain in the open
position, shown in FIG. 3. Assembly 54 is inserted into bay 98 by
positioning first rail 61 between upper rail guide 102 and lower
rail guide 104, and similarly positioning second rail 62 between
the upper rail guide and lower rail guide (not shown) provided on
the opposite side of bay 98. The hard drive assembly 54 loaded into
the lower bay 98 can rest on the bottom of case 100, therefore
eliminating the need for lower guide rail 104. Thus, only upper
guide rail 102 is used to guide assembly 54 into bay 98 and ensure
proper electrical connections. Hard drive assembly 54 loaded into
the upper bay 98 utilizes both upper and lower guide rails 102,
104.to ensure proper alignment and to provide support for the upper
drive assembly 54 when the lower drive assembly 54 is removed.
As shown in simplistic form in FIGS. 5A-5C, assembly 54 can be
pushed deeper into bay 98 by applying a force in direction A at
about the location of axis 82 on the face of handle 78. Handle 78
shown in FIGS. 1-4 has a flat front surface such that when assembly
54 is mounted into bay 98, handle 78 lies flush with the front
surface of case 100 of server 50. However, when handle 78 is in the
open position, the surface of handle 78 is at an angle relative to
the direction of rearward force (i.e. direction A) required to push
assembly 54 into bay 98. By applying the insertion force at the
location of the axis of rotation, a rearward force can be applied
to assembly 54 as a whole, without disturbing the open position of
handle 78. Alternatively, handle 78 may be provided with a slight
contour at the location where the insertion force is to be applied
so that when handle 78 is in the open position, the front surface
of handle 78 at that location is orthogonal to arrow A, thus
improving the feel of operation.
Handle 78 also includes cam 90, which protrudes beyond the right
edge of hard drive 58. At a point during the insertion of assembly
54 into bay 98, protruding cam 90 makes contact with shoulder 108
provided on the side of bay 98, as shown in FIG. 5B. After cam 90
makes contact with shoulder 108, the continued application of
insertion force causes hard drive assembly 54 to move rearward into
the bay 98 and additionally causes handle 78 to rotate about axis
82 to move from the open position to the closed position. As shown
in FIG. 5C, just as assembly 54 is fully inserted into bay 98,
handle 78 rotates such that first latch 84 engages first notch 92,
locking handle 98 into the closed position. At this same time,
second latch 88 filly engages second notch 94. First and second
latches 84, 88 securely retain hard drive assembly 54 in proper
connection with bay 98. The lever action created by cam 90
additionally assists in providing leverage to smoothly and
accurately mate hard drive 58 to bay interface 59.
To remove assembly 54, a user pulls on latch pull 86, applying
force in the direction of arrow B, shown in FIG. 5C. This force
would cause portion 87 of latch 84 to bend, thereby disengaging
latch 84 from notch 92. After latch 84 is disengaged and the user
continues pulling on latch pull 86, handle 54 then rotates from the
closed position to the open position, leaving latch 84 in the
position shown in FIG. 5B. The rotation of handle 78 causes second
latch 88 to disengage from second notch 94. While the user applies
a force on latch pull 86, handle 78 also acts as a lever to pull
assembly 54 out of bay 98. Cam 90, which abuts shoulder 108,
corresponds to the fulcrum, and the point where handle 78 connects
to axis 82 corresponds to the load. The removal force applied to
latch pull 86 assists in removing assembly 54, and, in particular,
provides additional leverage for smoothly separating the electric
interface connection between hard drive 58 and hard drive bay
98.
FIG. 6 illustrates a rear view of server 50 with case 100 partially
removed. Fans 120 are positioned directly behind hard drive bays
98. Fans 120 create a high pressure air flow from the front of
server 50 to the rear of server 50 by pulling ambient air through
holes 80 in face plates 72 of each hard drive assembly 54. This
cooling air flow then passes over and under each hard drive 58,
uniformly cooling the circuit boards and hard drive mechanisms of
each hard drive 58. Rear ventilation holes 122 allow the cooling
air to exit the rear of case 100. Because hard drives 58 are
densely packed in the low profile 2U case 100, very little room
exists between each drive 58 to allow air to flow. However, the
above-described structure of the present invention, as illustrated
in FIG. 7 enables effective cooling by creating air flow above and
below each hard drive assembly 54, with the advantage of having
five "hot swappable" half-height hard drives for storage.
In accordance with one aspect of the present invention, handle 78
advantageously provides an efficient mechanism for easily inserting
and removing hard drive assembly 54 from hard drive bay 98. This
mechanism utilizes cam 90 for effectuating both proper latching of
first and second latches 84, 88 during insertion, as well as easy
disengagement of latches 84, 88 and removal.
In accordance with another aspect of the present invention, hard
drive chassis 60, including rails 61, 62, retaining portion 70, and
handle 78, effectively provides a compact, yet simple and precise
mechanism for mounting hard drives 58. Hard drive chassis 60
provides an effective carrier and mounting mechanism for standard
size hard drives, with a minimum of additional structure, thereby
enabling very high density packing of components in a compact
server case 100.
Rails 61, 62 advantageously provide a solid support for hard drive
58, both when hard drive 58 is mounted in the hard drive bay 98 and
when drive 58 is removed from the computer and is being carried
about. At the same time, rails 61, 62 do not increase the overall
height of the drive and do not interfere with the free flow of
cooling air over the top and bottom surfaces of drive 58. Rails 61,
62 can be used in conjunction with rail guides 102, 104 to provide
very accurate mounting and removal of drive assembly 54 during hot
swapping. This helps to ensure stable connections between the
connection interface on hard drive 58 and the connection interface
in the drive bay 98 and helps prevent damage to the pins in
connection interface.
While the hard drive assemblies and mountings described above
consume most of the available space in the front of case 100 of
server 50, FIG. 6 illustrates several other components which are
arranged in the rear of case 100. For clarity, not all components
and connections are shown, and many of the components shown include
only simplistic detail.
Motherboard 124 is a printed circuit board onto which dual
processors 126, 127 are mounted. Such processors 126, 127 are well
known in the art and may be, for example, Pentium-type processors
manufactured by the Intel Corporation. RAM memory 126 is also
installed onto motherboard 124. Parallel port 130, serial port 132,
and mouse and keyboard ports 134 allow external devices to be
attached to server 50. Power supply 136 provides power to the
entire system.
Server 50 also provides expansion slots for up to two expansion
cards. Because of the low profile of case 100, expansion cards 138,
140 are mounted horizontally. Upper expansion card 138 (shown in
FIG. 6) plugs horizontally into upper expansion slot 142 and is
held in place by retaining clip 148. Lower expansion card 140 (FIG.
7) plugs into a lower expansion slot (not shown), slightly offset
from upper expansion slot 142. Upper and lower expansion cards 138,
140 may be accessed by external devices through expansion card
access ports 144, 146, respectively. As can be seen in FIG. 6, the
various components of server 50 are very densely mounted in the
minimal space available in case 100. In particular, expansion cards
138, 140 are mounted very close to power supply 136, restricting
the design of the mounting structure for cards 138, 140.
FIG. 7 illustrates a close-up view of the retaining clip 148
mounted on case 100. FIGS. 8A-8D illustrate retaining clip 148 from
multiple perspectives. For clarity, power supply 136 is not shown
in FIG. 7, but would normally be mounted. alongside flanges 150 and
be secured to case 100 with a screw through eyelet 152. Retaining
clip 148 includes a body portion 153, a first flange 156, a second
flange 154, a top flange 158, and a stabilizing projection 160.
Expansion card 138 is provided with an edge connector, which is
inserted into expansion slot 142 and provides mounting support for
that edge of card 138. One corner along the opposite edge of card
138 includes a mounting bracket 164. Mounting bracket 164 is used
to secure that edge of card 138 to case 100. In the prior art,
mounting bracket 164 would be secured by inserting a screw in the
x-direction through a notch or hole in bracket 164 to case 100.
However, in case 100, when power supply 136 is mounted, power
supply 136 inhibits access to mounting bracket 164, making it
difficult to access the screw using a screwdriver. Expansion card
140 is mounted to an expansion slot beneath expansion slot 138, and
poses similar difficulties in attaching mounting bracket 166 to
case 100.
Thus, the present invention provides retaining clip 148 to quickly
and easily stabilize the free ends of expansion cards 138, 140.
After expansion cards 138, 140 are inserted into their respective
expansion slots, retaining clip 148 is inserted into notch 168 on
the side of case 100 such that first flange 154 prevents unwanted
movement of mounting-bracket 166 on lower expansion card 140, and
second flange 156 prevents unwanted movement of mounting bracket
164 on upper expansion card 138. In particular, flanges 154, 156
prevent cards 138, 140 from moving in the x-direction, which may
result in a disconnection of the edge connectors to the expansion
slots.
Retaining clip 148 provides the added advantage of simple
installation. No screws or tools of any sort are needed; clip 148
is simply placed onto notch 168 such that stabilizing projection
160 and body 153 straddle notch 168 on either side of case 100. If
desired, stabilizing projection 160 and body 153 can be formed to
"pinch" case 100, thereby maintaining clip 148 in its proper
mounted position.
Slot 170 is provided in case 100 and is adapted to receive table
172 provided on the bottom end of second flange 154, thereby
providing additional stability for retaining clip 148. An
additional slot (not shown) can also be provided to mate with tab
174 on the bottom end of first flange 156. The bottom edge of body
153 may rest on a shoulder portion of case 100, providing vertical
support for clip 148. Clip 148 is also easily removable, in the
event that one of the expansion cards 138, 140 is replaced.
Applicants have implemented aspects of the present invention in
constructing a server 50, which can be mounted in a 2U rack, yet is
capable of accepting up to six half-height hard drives. (The
embodiment shown in FIG. 1 includes only five hard drives,
reserving the last bay 98 for floppy drive 56.) In this embodiment,
the entire server 50 measures 3.500" tall. The upper layer of
casing is formed of thin gauge steel measuring just 0.047" thick.
The lower layer of casing is formed of 0.039" thick steel. When two
half-height hard drives, 1.625" thick each, are mounted within this
structure, there remains only 0.164" of clearance for air to
flow.
Ideally, equal spacing is provided above and below the upper and
lower hard drives. Thus, where the upper and lower surfaces of the
hard drives define upper and lower planes of the hard drives, the
upper plane of the upper hard drive is spaced from the upper layer
of casing by approximately 0.055", the lower plane of the upper
hard drive is spaced from the upper plane of the lower hard drive
by approximately 0.055", and the lower plane of the lower hard
drive is separated from the lower layer of casing by approximately
0.055".
The hard drive structure in accordance with the present invention
enables very precise loading of "hot swap" half-height hard drives,
while preserving adequate airflow over both the tops and bottoms of
both stacked hard drives.
Although the invention has been described with reference to
particular embodiments, the description is only an example of the
invention's application and should not be taken as a limitation.
For example, server 50 shown in the figures has a 2U profile and is
used in conjunction with stacked half-height drives. However, a
server in accordance with this invention may also be formed to fit
in a 1U size rack. In this case, a single layer of half-height
drives are used. Various other adaptations and combinations of
features of the embodiments disclosed are within the scope of the
invention as defined by the following claims.
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